1. Field of the Invention
With respect to the classification of art as established in and by the U.S. Patent and Trademark Office, this invention is believed to be found in the general class of pressure regulators, pressure indicators and flow totalizers used with tank-type containers of oxygen.
2. Description of the Prior Art
A careful pre-Ex search was made in the U.S. patents and particularly for visual indicators for use with oxygen tanks. Rotary indicators with a visual readout or indication are very old. These indicators are usually with incandescent lamps and with the electrical energy used therewith, potential sparking at the contacts may occur. The possible presence of oxygen is noted so that in the present invention there is no possible production of a spark. The use of pressure regulators is well known and the diaphragm control of pressure is conventionally provided with a threaded turning control of the diaphragm. These regulators conventionally have a dial with a rotatable needle that indicates the pressure. The dial is usually quite small and for a user of oxygen may be quite difficult to read. The present invention provides an LED display of the pressure regulation so that the user can easily avail himself or herself of a desired or required pressure release. With electronic signal generation, these same signals may be sent to other control devices to make the pressure level with control by automatic means.
Pressure is usually read by a moving rotary dial in a pressure gauge. The common and very reliable pressure-indicating gauge utilizes a curved tube (Bourdon) device which as it is actuated rotates a shaft and needle. This type of gauge is difficult to read because of the usually small dial size. Totalizers are not new, but so as to assure the user of the oxygen bottle or tank it is comforting to have knowledge of the amount of gas used and as a consequence what amount still remains. Linear display devices are also known. These devices usually use a light ball in a vertical tube.
In the pre-Ex search, the following patents were found:
______________________________________ Patent No. Inventor Issuing ______________________________________ 737,296 Taylor 08-25-03 2,295,869 Seaman 09-15-42 2,452,344 Addorisio 10-26-48 3,319,623 London 05-16-67 4,016,536 LaChappelle 04-05-77 4,107,661 Crosby 08-15-78 4,197,650 Bailey et al 04-15-80 4,275,393 Johnston 06-23-81 ______________________________________
Taylor discloses a device for testing lung pressure and capacity utilizing a series of lights for indicating specific pressures or volumes. Seaman shows a neon sign having a switch provided with wiping contacts to activate specific sections of the sign. Addorisio shows an automobile speedometer having a needle providing wiping contact for a plurality of lights. London discloses a blood pressure monitor having two species of indicating lights, one controlled by a linear manometer and the other by a pivoted needle. LaChappelle shows another speedometer needle providing wiping contact for an indicating light. Crosby shows yet another meter pointer position indicator. Bailey et al shows another column gauge. Johnston shows a needle position indicator for a pressure gauge.
In the above-identified art there is no showing of a digital readout using LED's for the display. Rotary needle display is well known, but the use of an extending shaft or rod is novel. On this rod or shaft is carried the S-curved light conductor which is free at both ends so as to avoid any and all possible frictional contact and possible inaccuracy. As to be hereinafter more fully described in conjunction with the drawings, the rotary devices all contemplate the feeding of a light signal through a bent optic rod carrying this light signal to a light-receiving means whereat an electrical signal is sent to an enclosed reed switch which is actuated so as to send this signal to a microprocessor. This signal is converted to a signal to an LED readout display. The emitting light source is usually an infrared LED using low electrical voltate and energy, with the battery (self-contained) lasting for many months of use. This light is conducted by a bent rod or fiber optic which is small in size and weight. The rotatable shaft of the pressure regulator and pressure gauge carries this bent rod or fiber and because of the light weight the action of the moved shaft is not affected by this additional member. A special shaft is provided for this regulator and gauge by which the light-conducting rod is mounted in a desired oriented condition.